Fuel Delivery and Air Induction: Description and Operation

System Description:

This vehicle is equipped with a 1,308cc (80 cubic inch) displacement, 2 rotor, rotary gasoline engine, and a computer controlled electronic fuel injection system (referred to as EGI - electronic gasoline injection). The system maintains an air/fuel mixture as close as possible to the ideal stoichiometric ratio, for all operating conditions. Fuel is supplied to the injectors at high pressure by an electric fuel pump in the tank. The computer monitors various sensors mounted on the engine, including an exhaust gas oxygen sensor, then uses this information to determine the amount of fuel needed. The computer energizes the injectors for varying lengths of time, depending on the amount of fuel required. The intake manifold system, referred to as "Variable Dynamic effect Induction" system (VDI) is designed to take advantage of pulsations in the intake manifold to help improve low speed torque. Also, an auxiliary port in the engine is fed through an "auxiliary port valve" as part of what Mazda calls the "6-Port Induction (6PI) system", to help increase high speed power.


The primary fuel and intake components are covered in this section. For information regarding electronically controlled devices, the computer, and its functions, see Computers and Control Systems.

The fuel and intake system consists of the following:

Accelerator pedal and cable
Air cleaner, intake air ducts and associated parts
Auxiliary port valve (6-Port Induction System)
Bypass air control valve (BAC valve)
Dashpot
Double throttle diaphragm
Fuel filter
Fuel hoses
Fuel injectors
Fuel tank
Fuel pump
Fuel pump relay
Fuel pump resistor relay
Fuel pressure regulator
Fuel rails (delivery pipes)
Intake manifold (variable dynamic induction system)
Pulsation damper
Throttle body
VDI valve